黃金閱讀 The Geologic History of the Mediterranean - 英檢

第二段
Another task for the Glomar Challenger’s scientists was to try to
determine the origin of the domelike masses buried deep beneath the
Mediterranean seafloor. These structures had been detected years earlier
by echo-sounding instruments, but they had never been penetrated in the
course of drilling. Were they salt domes such as are common along the
United States Gulf Coast, and if so, why should there have been so much
solid crystalline salt beneath the floor of the Mediterranean?
第三段
With question such as these clearly before them, the scientists aboard
the Glomar Challenger processed to the Mediterranean to search for the
answers. On August 23, 1970, they recovered a sample. The sample consisted
of pebbles of gypsum and fragments of volcanic rock. Not a single pebble
was found that might have indicated that the pebbles came from the nearby
continent. In the days following, samples of solid gypsum were repeatedly
brought on deck as drilling operations penetrated the seafloor.
Furthermore, the gypsum was found to possess peculiarities of composition
and structure that suggested it had formed on desert flats. Sediment above
and below the gypsum layer contained tiny marine fossils, indicating
open-ocean conditions. As they drilled into the central and deepest part of
the Mediterranean basin, the scientists took solid, shiny, crystalline salt
from the core barrel. Interbedded with the salt were thin layers of what
appeared to be windblown silt.

What is the main purpose of paragraph 3?
(1)To describe the physical evidence collected by Hsu and Ryan.
(2)To explain why some of the questions posed earlier in the passage could
not be answered by the findings of the Glomar Challenger.

答案是(1) 為什麼不是(2)呢?

謝謝大家!

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